Copper oxide rectifier



Aug. 23, 1932. P. M. HENGSTENBERG 1,872,947

v COPPER OXIDE RECTIFIER 4 Filed'Aug. 22,. 192e mvENToR Paz/ZMH'ngsenberg.

AT'TQRNEY Patented Aug.4 23, 1932 UNITED STATES PATEiuT oFFlca PAUL M. HENGST'ENBERG,

or WILKINSB'URG, ruuusvrvaiimjassreuon To WEST- INGHOSE ELECTRIC & MANUFACTURING COMPANY, ACORIPORATION PENN- SYLVNIA comme oxinn REc'rIFIER Applieationrled August 22, 1928.l Seria1.No..301,275.

tions thereof out of contact withone another.

A further object of my invention is to provide a rectifier` of the metal disc type wherein the discs are held in cooperative engagement by a central tie bolt extending through perforations in the disc and wherein the material of the discs adjacent to the perforations therein is maintained in spaced relation for preventing contact of the edges of the perforation of one plate with those of an adjacent plate.

A further object of my invention is to provide a. rectifier of the oxidized disc type wherein the discs of one character are of larger diameter than those of the discs disposed between them, in order to offset the marginal edges of the. discs and thereby prevent any portion of the edge of one disc from engaging a portion of the edge of a cooperative adjacent disc.

These and other objects that Will be made apparent throughout further description of my invention, are obtained by means of a rectiiier device hereinafter described and illustrated in the accompanying drawing wherein: 4 v

Figure 1 is a vertical section through a rectifier unit embodying features of my invention.

Fig. 2 is a vertical section through a pair of cooperating discs constituting a part of the rectifier, and

Fig. 3 is a transverse section of the rectifier taken on the line IHIII of Fig. 1.

Rectifiers of the metal disc type usually comprise a plurality of metal discs prefer` ably made of copper and which are coated on one side and on all edges thereof with copper oxide. Discs made of an impressible materialpsuchas soft nickel or lead are usually disposed between the copper discsin such manner'that'current passes in series through the lead ,or `nickel discs, by passing' first through the bare surface of the copper disc and thence'tliroughthe copper oxide on onefv l face ofthe copper disc to the lead or nickel disc in engagement therewith.` Any desired i number of lead `and co per discs may be arranged.alternately, asjindicated in Fig. 1 in order to secure the capacity desired in the i rectifying` unit. A. soft metal tact with the oxidized surfaces, in'order that the soft metal surface may conform with the irregularities in the oxidized surface and thereby produce an efficient conductive joint dis-c is usually placedin con'- os i or contacto` A rectitierof this character is l disclosedy in the copending application of ,AlfredArther-ton, filed December 31,1927, and assign-ed to the Westinghouse Electric & Mfg. Company.

It has been found discs sometimes become short circuitedr by reason of the contact of portions of the edges of 'the discs, in the event that the copper Voxide coating of the outer marginaledges of that the lead and opper the discs and the edges of the perforationsf` is chipped oit during manufacture and assembly of .the rectifier units. In order to obviate this difficulty and to facilitate they centering of the disc, the lead or nickel discs are made of smaller diameter ,than the copper discs, thus so oit-setting the marginal edges of the discs that they cannot come into contact with one another. I In addition7 the copper discs are counter bored adjacent the perforation, and the lead discs are embossed .Y

adjacentv the perforation in a manner toseparate the lportions of the copper and lead discs adjacent the perforations, as Will be hereinafter more fully described.

lieferring to the drawing, the rectifier unit comprises a plurality of copper discs 4, that arc provided with an oxidized surface or coating that covers one surface of the disc and the'niarginal edges thereof, as indicated in Figs. 1 and 2. The unoxidized surface ofr the discs 4- areprovided Wit-ha counter bore or depression 6 that ispreferably made by soA counter boring Ithe disc adjacent the perforation 7 therein. The depression is counterl `bored instead of being pressed, because it has been found -that forming the depression by a pressing .operation distorts thesurfaces of the disc.

' Between .each copper disc, a lead or nickel vcent oXidiZed'sui-face of the copper disc 4.

It- Will be seen, by reference to Fig. 1, that the "oxidized edges of the perforations in the copper discsare spaced vfrom the` edges ofthe perforations in the lead discs and thus contact'therevi'itli vis obviatedf Since the outer marginal edges of the lead and copperdiscs are off set by reason of their different diameters, there is no chance for portions'of 'the outer marginal edges of the oxidized disc to come iii contact with or short circuit, the lead or nickel disc in the event that the oxidized-coating is chipped off through assembly or manufacture.

` The discs are retained in assembled relation by means of a tie bolt 13 that extends through the perforations in the discs 4 and 8 and insulated therefrom by means of an insulating bushing 14 that surrounds the bolt. End plates 15 and 16 are provided for tightly clamping the discs iii assembled relation and terminals 17 and 18 are provided for the electrical conductors. y

From the foregoing, vit is apparent that cent disc and with a. de ression onk the other side to rovide an insu ating space between p it and t e other adjacent disc.

3. A Lrectifier comprising two groups of j perforated cooperating current-rectifying discs, the discs of one group beingdisposed in alternate side-to-side relation to the other group and each having the portion surrounding the perforation offset to provide a de-.. pression onone side and -a boss onthe other,

side, vthe discs of the other'group'being'severally provided! 'With' a' counter-bored depression adjaoent to the perforation to receive the boss of the adjacent disc.

In testimony whereof, I have hereunto subscribed my name this 13th day of August 1928.

PAUL HEGSTENBERG. y

kno

simple means are provided for centering the discs and for preventing the oxidized edges of the copper plates from coming in Contact with vthe edges of the,v lead or nickel platesv The method employed is inexpensive, and the dimensions of the assembled unit are Vnot lincreased by the reason of an improvement in the design of the rectifier unit.

I claim as my invention:

1. A rectifier comprising a pair of pera forated cooperating current-rectityiiig discs, one of which is oxidized on one surface and counter-bored adjacent to the perforation onn the unoxidized side and the other' of which is embossedto provide a Vraised portionitting Within the said counter-bored,depression in l the first disc.

2. A rectifier comprising a' pluralit of perforated cooperating current-recti ying discs, alternate discs being severally provided, on one side, With a vcounter-bored de-y pressionadjacent to the perforation, yand the intervening discs being severally provided with an odset portion'forming a boss on one side to fit into the depression on one adjay iso 

